HAINESPORT, N.J. — It looks like a toy, but the bracelet locked around Bob Melnick’s wrist gives his wife some peace of mind: If this Alzheimer’s patient wanders off and gets lost, he’s wearing a tracking beacon to help bring him home.

Wandering is one of the most frightening symptoms of advancing dementia, and the Alzheimer’s Association estimates it will happen to nearly 60 percent of patients.

A mini-industry of technologies promises to find lost Alzheimer’s patients — from simple radio-wave beacons that cost $10 a month for batteries, to more-sophisticated GPS devices that can cost hundreds of dollars.

Little if any independent research has been done to help determine which systems work best in different environments, and therefore are best suited to different families.

“These technologies need to be evaluated,” said Majd Alwan, director of the Center for Aging Services Technologies, a coalition of government, universities and high-tech companies.

Location mattersAmong considerations are where the patient lives, added Henry Kautz of the University of Rochester, who is helping develop next-generation systems. For example, the accuracy of GPS devices depends on access to satellites powering the navigation tool.

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Whatever the transmitter, there’s the question of how to ensure the patient doesn’t wander off without it. Some systems require carrying cell phones; others come in hard-to-remove jewelry; one company sells sneakers implanted with a GPS chip.

For families, there’s little guidance on how to find, or choose from, the devices.

Dolores Melnick learned almost by accident that her county sheriff’s department offered the radio beacon through a program called Project Lifesaver, when a relative stumbled across an Internet site.

Melnick already was enrolled in the Alzheimer’s Association’s low-tech Safe Return program. For $20 a year, the hot line faxes photos and descriptions to law enforcement when a patient is reported missing. Patients also wear a stainless steel tag listing a number to call if they’re found wandering.

But after getting briefly separated in an airport, Mrs. Melnick liked the idea of more active tracking, too. When she snapped the bracelet on her husband, “He said, ‘Oh, this is so you don’t lose me!”’

Stay tuned: Kautz says next-generation sensors promise to help dementia patients help themselves, guiding those with early-stage Alzheimer’s on city buses or reminding later-stage patients how to wash their hands.